1. VXLAN GPE Extension for Packets Exchange Between Control and User Plane of vBNG
Lu Huang, China Mobile
Shujun Hu, China Mobile
Michael Wang, Huawei
Ting Ao, ZTE

2. Problem to be addressed
For China Mobile’s metro network evolution, we choose to separate control plane and user plane of the traditional BNG ( Broadband Network Gateway, or called BRAS, Broadband Remote Access Server)
BNG-CP
BNG-UP
Service
Interface
Traditional BNG
Between BNG-CP and UP, service interface is used to transmit PPPoE/IPoE authentication packets from UP to CP. We prefer to use VxLAN to encapsulate user’s packets. Furthermore, user’s port information on BNG-UP should be reported to BRAS-CP
For TE, TS, LB, we need the BGP community information of a specific flow.
We usually design several communities for one AS.
BRAS-CP
VxLAN
No standard way for carrying port information in VxLAN header
PPPoE
BRAS-UP
PPPoE
Port information includes:
device ID, slot ID, subcard ID, port ID
User

3. ifIndex ( 32bit, speified in [RFC2863])
Proposed solution
Extend VxLAN-GPE header to meet the requirement because it seems leverage the flexibility and complexity.
Flag
Reserved
New Next protocol =
vBNG service header
VNI
Next protocol
Node ID
Slot ID
Subcard ID
Port ID
Port type
VXLAN GPE Header
vBNG Service Header
An optional format for port information
For TE, TS, LB, we need the BGP community information of a specific flow.
We usually design several communities for one AS.
Flag
Next protocol
Reserved
Node ID
ifIndex ( 32bit, speified in [RFC2863])
It’s a standard way to indicate a port/interface. But it can’t explicitly show the port’s location. CP should maintain a mapping table between ifIndex and physical port exactly same as UP. Should define a way to generate this table, UP or CP make the decision? It’s relatively more complex than the explicit way

4. Example of PPPoE dialup process
For TE, TS, LB, we need the BGP community information of a specific flow.
We usually design several communities for one AS.

5. Next Steps Welcome your comments and suggestions
Request for WG adoption
For TE, TS, LB, we need the BGP community information of a specific flow.
We usually design several communities for one AS.

6. Thanks